Abstract

A novel electroless (autocatalytic) gold plating bath containing sodium L-ascorbate as the reducing agent has been developed. A suitable bath composition was formulated based on the results of an electrochemical study in which were determined at a gold electrode the anodic polarization curves of various reducing agents and the cathodic polarization curves of sodium tetrachloroaurate (III) dissolved in solutions of sodium sulfite and/or sodium thiosulfate.A typical bath containing 0.0125mol/dm3 sodium tetrachloroaurate (III), 0.1mol/dm3 sodium sulfite, 0.1 mol/dm3 sodium thiosulfate, and 0.25mol/dm3 sodium L-ascorbate, was operated under moderate conditions, typically at a pH of 6.0 and 333K. The rate of gold deposition obtained with this bath was in the same range or greater than that obtained with the classical cyanide-borohydride bath. The deposition rate of the new bath depended on both the ascorbate and gold concentrations, and the gravimetrically determined deposition rate was found to correspond well with the rate estimated from electrochemical polarization measurements.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.